1. Field of the Invention
This invention relates generally to outdoor kitchens and cookers, and more particularly to an outdoor multi-method cooker for preparing a wide variety of different foods at the same time using selective convection, radiant, or conduction cooking operations with or without smoke, or combinations thereof, using a single heat source.
2. Background Art
Mobile outdoor kitchens and cookers for cooking different foods at the same time are known in the art. In the early 1900's wheeled “rolling military kitchens” or “Field Kitchens” such as disclosed in Gunn, U.S. Pat. No. 1,244,489, Baldwin, U.S. Pat. No. 1,328,071 and Morrison, U.S. Pat. No. 1,422,603, were developed for feeding army troops.
Barbecue grills have become increasingly popular in recent years because of the interest in outdoor cooking. Conventional charcoal grills utilize a quantity of charcoal placed in the lower portion of the grill with a cooking grid supported at the upper portion. The charcoal serves as the heat-producing means for the food being cooked. Conventional gas grills include a burner assembly adjacent the lower portion of a firebox with a cooking grid supported along the upper edge and lava rock located between the cooking grid and the burner assembly. The lava rock absorbs the heat from the burning gas and provides a generally uniform heat-producing means for the food being cooked. Cooker/smoker type outdoor grills and ovens have also become increasingly popular for cooking of meat and other assorted food in an outdoor setting wherein the food can be roasted over a grill and cooked by the heat from hardwood or charcoal briquettes burning under the grill.
However, a common problem with these types of cookers and grills is that grease, sauce and drippings from the food being cooked and other combustible particles fall directly into the charcoal, lava rock, or fire, causing flare ups and hot spots within the grilling chamber and irregularities in cooking temperatures which can result in charring and burning of the food.
Some cooking apparatus have been developed which avoid the difficulties discussed above by conducting the hot gases from a hardwood fire into a cooking chamber where it is circulated before being exhausted, and collecting the excess renderings and drippings in pans disposed below the meat.
Deaton, U.S. Pat. No. 4,076,008 discloses a barbeque oven wherein meat is suspended on a perforated food rack within an enclosed, heat retaining housing, and heat and smoke from a firebox adjacent one end of the housing is directed along the length of the housing within a tempering passageway and then up, around the meat, and along the length of the housing in the opposite direction to an exit flue fixed to the top of the housing adjacent said end of the housing. A baffle divides the housing into upper and lower portions for directing the above-described flow of smoke and heat, and insulation located intermediate the food rack and the opening connecting the firebox and the lower portion of the housing prevents direct radiation from the firebox from striking meat on the food rack. Warming closets with a flue for controlling the temperature within said warming closets are provided adjacent said end of the housing above the firebox.
Cox, Jr., U.S. Pat. No. 4,700,618 discloses a portable meat smoker cooking unit having a fire box and a smoker oven vertically and laterally offset from the fire box. The smoker oven has an upper enclosed volume containing meat to be cooked and a lower enclosed volume which opens directly to the fire box. The upper and lower volumes are separated by a hot pan drain wall. An adjustable damper is provided between the upper volume and the fire box to control the temperature and the smoke density within the upper volume. A top having a heating plate may be placed over an opening in the fire box to define an oven volume for radiant heat input.
Some cooker and grills use heat transfer through radiation together with convection heating from the circulating air and conduction heating through the grill's surface to perfect the carmelization process. Many of these types of grills do not adequately allow a means for regulating the intensity of heat needed to properly grill various foods. Reducing the temperature of the heat source can diminish the effect of radiation heat transfer and leave only relatively inefficient convection heating to cook the food. Air blowers and plenum chambers have also been used to force air past the heat source to improve heat transfer efficiency, however, with many of these types of cookers, after the air is forced past the food product it is exhausted to the atmosphere and no longer redistributed within the apparatus to aid in the grilling process or for other cooking operations. The achievement of uniformly cooked meat and the efficient use of fuel and energy are some continual problems associated with the operation of outdoor cookers and grills.
Higgins, U.S. Pat. No. 4,418,615 discloses a convection barbecue pit wherein heated smoke from a firebox passes through a flue into a cooking chamber, which has a discharge duct and fan in the ceiling thereof to draw the smoke entering the cooking chamber through a suction port to exhaust the smoke lade gases. The flue may be set to exhaust smoke around the cooking chamber when the pit is in an evacuation mode.
Kalthoff, U.S. Pat. No. 4,791,909 discloses a smoker oven for cooking and smoking food including a housing with an uppermost and lowermost cooking chamber. Hot, smoke laden air is produced and circulated inside the housing, and means are provided for directing the flow of circulating air horizontally through each chamber, passing the air through the uppermost and lowermost chambers in essentially opposite horizontal directions. Means for baffling and diffusing the airflow into each cooking chamber provide uniformly distributed horizontal airflow through each cooking member.
Archer, U.S. Pat. No. 5,000,085 discloses an air slot cooking grill which recirculates its hot air for grilling foods. The cooking device is formed from an enclosure having a bottom, side walls and a removable top. A housing abuts a side wall of the enclosure and communicates fluidly with a chamber through an air flow opening. A blower located within the housing chamber recirculates air throughout the enclosure. A jet curtain plate containing various slot widths is mounted in the heat supplying space of the enclosure and spaced apart and above the heat supplying element. The slots yield streams of air having different velocities at different areas of the jet curtain plate such that certain areas of the grill have various cooking speeds. After the hot air heats the food on the grill, the air flows rearwardly and downwardly into a return plenum and the heated air is drawn by a fan impeller horizontally into the heating plenum where it traverses and absorbs heat from the heating element. To complete its recirculating path, the heated air is then directed to the air slot openings in the jet curtain plate and redirected back to the grill. Although this patent recirculates hot air within the enclosure of the barbecue, it is only adapted for a heating element and not for wood or charcoal.
IIagan, U.S. Pat. No. 5,996,572 discloses a turbo-charcoal barbeque having a detachable turbo unit, an adjustable rotisserie ensemble, a moveable charcoal tray, removable ash trays, and a fire screen. The turbo unit is positioned to recirculate hot air from underneath the charcoal tray and redistribute the hot air to the upper and lower areas of the grill. The turbo unit and rotisserie are driven by a 12 volt motor or from an electrical outlet using a transformer.
Lloyd et al, U.S. Pat. No. 6,651,646 discloses a barbecue grill having a heating compartment and a plenum chamber disposed proximate to the heating compartment. The plenum chamber has a central vent for providing access to the central portion of the heating compartment and a pair of opposed side vents to provide access to the two opposed side portions of the heating compartment. A recirculation fan is disposed proximate to the central vent. The recirculation fan is adapted to draw hot gases from the central portion of the heating compartment into the plenum and drive those gases via the plenum into the side portions of the heating compartment via the pair of opposed side vents.
The present invention is distinguished over the prior art in general, and these patents in particular by an outdoor multi-method cooker for preparing a wide variety of different foods at the same time using selective convection, radiant, or conduction cooking operations with or without smoke, or combinations thereof, using a single heat source. The cooker has a horizontal central longitudinal chamber with a firebox at one end and a pair of stacks at the opposed end, a main oven, a pair of lateral smokeless ovens, a warming compartment, and a griddle above the firebox, all disposed transversely on the longitudinal chamber in parallel spaced relation, and a steam table along the upper portion of the longitudinal chamber. The cooker operates on the principle of equalization of natural differential pressures caused by rising warmer air, similar to the draw created by the upper portion of a fireplace, for drafting hot gases or smoke laden hot gases from the combustion source and selectively routing it through passageways into and around the various components.